Atypical hemolytic uremic syndrome in human immunodeficiency virus-1-infected children

We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters, both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains unknown and the role of HIV infection in its pathogenesis, although possible, is unclear. Received March 5, 1996; received in revised form and accepted October 15, 1996     

Cyclic guanosine 3'3' monophosphate concentrations in pre-eclampsia: effects of hydralazine

Objective To elucidate the role of the L-arginine: nitric oxide pathway in pregnancy and pre-eclampsia.
Participants Pregnant women (nulliparous, age < 25 years). Normotensive pregnancy (   n = 22  ) was defined when blood pressure remained at levels of < 120/80 mmHg and there was no proteinuria. Women with pre-eclampsia (   n = 22  ) had blood pressure measurements of > 140/90 mmHg and proteinuria of > 300 mg/l. Nonpregnant normotensive women (   n = 22  ) were studied as controls.
Study Design Blood samples were taken for measurements of ionised calcium, atrial natriuretic factor, cyclic guanosine 3'5'monophophate (GMP), arginine and asymmetric dimethylarginine. Urine samples were collected for determination of cyclic GMP excretion. Cyclic GMP concentrations were also determined in 12 women with severe pre-eclampsia before and after treatment with hydralazine.
Results L-arginine, asymmetric dimethylarginine and atrial natriuretic factor were not different in any group. Cyclic GMP concentrations in plasma [0.94 (SD 0.23) nM] as well as in urine [50.1 (SD15.7)μM] were increased significantly (   P < 0.05  ) in normal pregnancy compared to nonpregnant controls [plasma mean 0.46 (SD 0.12) nM and urine mean 18.4 (SD 10.3) μM], but not in the pre-eclampsia group [plasma mean 0.48 (SD 0.10) nM and urine mean 24.1 (SD 14.5) μM]. Concentrations of cyclic GMP in plasma and urine increased significantly (   P < 0.05  ) in women treated with hydralazine.
Conclusions The differences in cyclic GMP concentrations may reflect differences in nitric oxide production. Hydralazine increases cyclic GMP concentrations in severely pre-eclamptic women. This action could explain the antihypertensive effect of hydralazine.     

Changes in retinoblastoma gene expression during cervical cancer progression

The role of tumour suppressor genes in the development of human cancers has been studied extensively. In viral carcinogenesis, the inactivation of suppressor proteins such as retinoblastoma (pRb) and p53, and cellular oncogenes overexpression, such as c-myc, has been the subject of a number of investigations. In uterine-cervix carcinomas, where high-risk human papillomavirus (HPV) plays an important role, pRb and p53 are inactivated by E7 and E6 viral oncoproteins, respectively. However, little is known about the in situ expression of some of these proteins in pre-malignant and malignant cervical tissues. On the other hand, it has also been demonstrated that c-myc is involved in cervical carcinogenesis, and that pRb participates in the control of c-myc gene expression. By using immunostaining techniques, we investigated pRb immunodetection pattern in normal tissues, squamous intraepithelial lesions (SILs) and invasive carcinomas from the uterine cervix. Our data show low pRb detection in both normal cervical tissue and invasive lesions, but a higher expression in SILs. C-Myc protein was observed in most of the cellular nuclei of the invasive lesions, while in SILs was low. These findings indicate a heterogeneous pRb immunostaining during the different stages of cervical carcinogenesis, and suggest that this staining pattern could be a common feature implicated in the pathogenesis of uterine-cervix carcinoma.     

Tissue weight and histologic alterations in pregnant rats submitted to malnutrition and chronic nicotine distress, and in their neonates

The effects of a gestational exposure of 80 rats Wistar EPM-1 to nicotine and undernutrition was examined. The weight and histological alterations on the liver and lungs was evaluated on the rats and their offspring. A significantly lower weight gain, including liver and lung weight, was observed in nicotine exposed groups. There was no alteration of the placental weight. Decidual necrosis and hepatic congestion was frequent in the rats. Lung emphysema was found in the neonates.     

Nonanatomic Thoracoscopic Wedge Resection for Diffuse Lung Disease and Indeterminate Pulmonary Nodule

Video technology has revolutionized thoracoscopy dramatically, considerably increasing its indications. The clinical charts of patients who underwent a video-thoracoscopic procedure during a 6-year period were reviewed. Any patient in whom lung wedge resection for diffuse disease or an indeterminate nodule was performed met the inclusion criteria. Early and long-term outcomes were analyzed. A total of 310 thoracoscopic procedures were performed in the 250 patients reviewed. Of these patients, 60 presented with diffuse lung disease and 71 with an indeterminate pulmonary nodule. The total morbidity among diffuse disease patients was 5% (one intercostal vessel hemorrhage and two air leaks). Overall mortality for this group was 11% and was related to previous respiratory status and underlying disease. Patients not requiring preoperative mechanical ventilation ended up requiring it postoperatively, for a crossover rate of 23%. There was no morbidity or mortality in patients who did not require mechanical ventilation. The therapeutic impact index (defined as the total number of patients divided by the patients in whom initiation or withdrawal of specific treatment was due to the biopsy result) for diffuse lung disease was 0.9. Regarding lung nodule resection, early morbidity was present in one patient, who developed a persistent air leak. Late morbidity was present in three patients, who developed persistent intercostal pain. Total morbidity was 5.6%. No mortality was observed for this group. Nonanatomic wedge resection via video-thoracoscopy for diffuse pulmonary disease and indeterminate lung nodule is feasible using minimally invasive methods. Morbidity and mortality are related to the underlying disease and the respiratory status; they are not necessarily due to the procedure.     

Angiotensin II type 1 receptor blockade ameliorates tubulointerstitial injury induced by chronic potassium deficiency

BACKGROUND: Chronic potassium (K+) deficiency, one of the well-known causes of renal tubulointerstitial injury, is associated with an alteration in vasoactive mediators including persistent generation of renal cortical angiotensin (Ang) II despite the suppression of plasma Ang II, and suppression of urinary nitrite/nitrate excretion. We tested the hypothesis that K+-deficiency-induced renal tubulointerstitial injury could be mediated by Ang II or a reduction in nitric oxide. METHODS: Rats were fed a K+-deficient diet (0.01% K+) alone, or with either losartan or l-arginine (L-Arg) in drinking water. Control rats were fed with a normal K+ diet (0.36% K+). At the end of 10 weeks, kidneys were excised and renal injury was evaluated. RESULTS: Serum K+ was similarly depressed in all three groups receiving the K+-deficient diet. Rats on the K+-deficient diet alone developed renal hypertrophy and tubulointerstitial fibrosis with an increase in tubular osteopontin expression, macrophage infiltration and type III collagen deposition. Administration of losartan significantly reduced renal hypertrophy and prevented tubulointerstitial injury in the cortex, although some medullary injury occurred. In contrast, administration of L-Arg did not attenuate tubulointerstitial injury in the cortex, despite a complete recovery of urinary nitrate excretion. Mild but significant improvement of tubular osteopontin expression and macrophage infiltration were observed in the medulla of L-Arg-treated hypokalemic rats. CONCLUSIONS: These results indicate that hypokalemic renal injury is mediated, at least in part, by Ang II via the Ang II type 1 receptor, with a lesser contribution mediated by a reduction in nitric oxide. Losartan may be beneficial in preventing hypokalemic tubulointerstitial injury.     

Hemorrhagic and Thromboembolic Complications after Bariatric Surgery in Patients Receiving Chronic Anticoagulation Therapy

Background Perioperative management of bariatric surgical patients receiving chronic anticoagulation requires an understanding of potential hemorrhagic and thromboembolic risks. The aim of this study is to evaluate hemorrhagic and thromboembolic complications in morbidly obese patients who are on oral anticoagulation treatment and subsequently undergo laparoscopic bariatric surgery. Methods The medical records of all laparoscopic Roux-en-Y gastric bypass (LRYGB) patients from June 2001 to March 2006 were retrospectively reviewed. In addition, data of patients who received chronic anticoagulation therapy with Coumadin and underwent laparoscopic Roux-en-Y gastric bypass was analyzed. Clinical parameters included length of hospitalization, hemorrhagic complications, thromboembolic complications, conversion rate, reoperation, and blood transfusion. Results During the study period, 1,700 consecutive patients underwent bariatric surgery for the treatment of morbid obesity. Of these, 21 patients were treated with chronic oral anticoagulation; 3 of the 21 (14%) had hemorrhagic complications: one patient had intraluminal hemorrhage and two patients had intraabdominal hemorrhage. Two patients required blood transfusion, and one patient underwent surgical reintervention. None of the 21 laparoscopic operations were converted to open procedures. There were no postoperative mortalities, and there were no thromboembolic events in this series. Conclusions Laparoscopic bariatric surgery can be performed relatively safely in morbidly obese patients who are treated with chronic oral anticoagulation. Even in the presence of bleeding, patients can be successfully treated without the need for reoperation.     

Behavior of the Common Bile Duct Diameter Before and 12 Years after Choledochostomy for Cholecystolithiasis and Choledocholithiasis. A Prospective Study

INTRODUCTION : In patients with common bile duct (CBD) stones, the diameter of the CBD is usually dilated. After surgery, the behavior of CBD diameter is not clearly known. OBJECTIVE : To determine at a late follow-up the width of CBD before and after choledochostomy for CBD stones. MATERIAL AND METHODS : In this prospective study, 39 patients with gallstones and CBD stones were included. They were 30 women and 9 men with a mean age of 52.6 years. In all ultrasound, determination of the CBD caliber before and 12 years after surgery was performed. RESULTS : The mean value of the inner diameter of the CBD before surgery was 11.6 and 12.3 mm in patients below or above 60 years, respectively. Measurement 12 years after surgery showed a mean decrease of nearly 50% of preoperative values, which was highly significant (p < 0.0001). However, either below or above 60 years, only 75% of the patients showed this decrease, whereas 25% remained unchanged. CONCLUSION : The dilated preoperative CBD returns to normal or near normal values in 3/4 of the patients after surgical exploration of the CBD and extraction of the stones.